Some embodiments described herein relate generally to systems, methods, and apparatus for wirelessly transmitting power.
As processor capabilities have expanded and power requirements have decreased, the number of devices operating independent of wires or power cords has increased. These “untethered” devices (also referred to as “wireless devices”) include, for example, cell phones, wireless headphones, wireless keyboards, smartwatches, building sensors, and RFID tags. These untethered devices, however, are often limited by their portable power sources (e.g., the life and/or capacity of their batteries). Furthermore, recharging the portable power sources of many untethered devices often requires the untethered devices to be temporarily coupled via a wire (e.g., a power cord) to an external power source, such as a wall outlet. Thus, during a recharging period, the untethered devices have limited mobility relative to the external power source. Additionally, a user of an untethered device typically needs to manually initiate and conclude a recharging process of the untethered device, which may be inconvenient.
Thus, a need exists for systems, methods, and apparatus that allow for convenient wireless powering of wireless devices.